Coupling device

ABSTRACT

A coupling device (100) for transferring a fluid is provided. The coupling device comprises a first housing (110), a tube portion (140) projecting into the first housing, and a second housing (200) displaceably arranged within the first housing. The coupling device further comprises a third housing (300) releasably connectable to the second housing and displaceably arranged within the first housing when connected to the second housing. In a first position of the second housing, the first and second channels constitute a passage which is sealed by the first and second sealing elements when the second housing and the third housing are connected. In a second position, the tube portion projects through the first and second sealing elements and into the sealed passage for enabling a transfer of fluid through the coupling device.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is the National Stage Entry under 35 U.S.C. § 371 ofPatent Cooperation Treaty Application No. PCT/EP2017/078619, filed 8Nov. 2017, the contents of which are hereby incorporated by referenceherein.

FIELD OF THE INVENTION

The present invention generally relates to the field of medical devices.More specifically, the present invention relates to a coupling devicefor transferring a fluid.

BACKGROUND OF THE INVENTION

During patient treatments, there may be a need of transferring one ormore fluids (blood, blood products, one or more medicines, etc.) toand/or from a patient. As the fluid often is supplied via an element(e.g. a needle, cannula, catheter, trocar, or the like) inserted intothe patient during treatments of this kind, it is desirable that theelement remains relatively fixed after insertion into the patient.Involuntarily displacements and/or movements of the element afterinsertion into the patient may arise in case the patient or any medicalstaff accidentally pulls a tube connected to the element. Furthermore,stumbling accidents of the patient and/or medical staff over a tubeconnected to an element may also lead to element displacements. It willbe appreciated that displacements of this kind of an element may notonly be painful for the patient, but may also lead to consequences ofthe treatment if the transferring of fluid due to the element'sdisplacement is not performed correctly. Furthermore, it should be notedthat pulling an element inserted into a patient with force could damagethe vessel of a patient. Furthermore, for a patient with a compromisedimmune system, a wounded vessel could lead to a serious infection.

In addition, in case of an accidental pulling of a tube for a transferof a fluid to a patient, it is desirable that any leakage of the fluidis mitigated. For example, if the infusion liquid is toxic, any leakagefrom a broken tube may be especially hazardous.

SUMMARY OF THE INVENTION

It is an object of the present invention to mitigate one or more of theabove problems and to provide a device for medical purposes which mayconveniently mitigate effects of a tube exposed to forces, e.g. pullingforces, and in particular when the tube is connected to an element fortransferring a fluid to/from a patient.

This and other objects are achieved by providing a coupling devicehaving the features in the independent claim. Preferred embodiments aredefined in the dependent claims.

Hence, according to the present invention, there is provided a couplingdevice for transferring a fluid. The coupling device comprises a firsthousing extending along a principal axis A. The first housing comprisesa first opening at a back end portion thereof and a second opening at afront end portion thereof. Moreover, the coupling device comprises atube portion extending from the first opening into the first housing.The coupling device further comprises a second housing which isdisplaceably arranged within the first housing along the principal axisbetween a first position at the front end portion of the first housingand a second position at the back end portion of the first housing. Thesecond housing comprises a first sealing element. Furthermore, thecoupling device comprises a third housing which is releasablyconnectable to the second housing and configured for displaceablearrangement within the first housing along the principal axis. The thirdhousing comprises a channel through the third housing and a secondsealing element arranged to seal the channel. In the first position ofthe second housing, the third housing is insertable into the firsthousing via the second opening thereof such that the first and secondsealing elements are configured to abut each other and sealinglyseparate the tube portion and the channel. In the second position of thesecond housing, the third housing and the second housing are connected,and the tube portion projects through the first and second sealingelements for connection with the channel for enabling a transfer offluid through the coupling device.

Thus, the present invention is based on the idea of providing a couplingdevice for transferring a fluid, wherein the coupling device may enablea transfer of fluid through the coupling device which is sealed to theoutside environment when the coupling device is connected, and aleak-free interruption of a transfer of a fluid in case the couplingdevice is disconnected. More specifically, upon connection of thecoupling device, first and second sealing elements firstly provide asealing upon abutment with each other. Thereafter, a transfer of fluidis enabled by the tube portion of the coupling device, projectingthrough (penetrating) the first and second sealing elements. Upondisconnection of the coupling device, which disconnection may betriggered by a pulling force applied to the third housing and the secondhousing of the coupling device, the second housing may be displaced fromits second (retracted) position to its first (extracted) position.Consequently, this results in a retraction of the tube portion from itsposition through the first and second sealing elements such that thesecond housing and the third housing subsequently become sealed again bythe first and second sealing elements, respectively. In other words, therespective first and second sealing elements may conveniently stop aflow on either side of the respective sealing elements upondisconnection/detachment of the coupling device. Hence, the couplingdevice of the present invention may provide excellent sealing propertiesand avoid leakage, both during a transfer of fluid through the couplingdevice as well as during an interrupted flow of fluid through thecoupling device as a result of a detachment or disconnection of thecoupling device.

It will be appreciated that the ability of the coupling device tomitigate any leakage of fluid is advantageous for reasons of safety. Forexample, in case the coupling device is provided for a transfer of atoxic liquid, any leakage from the coupling device may be particularlyhazardous. Hence, the coupling device of the present invention maysignificantly increase the safety of medical staff and/or patients.

Furthermore, the coupling device of the present invention isadvantageous in that it may save fluid by its advantageous sealingproperties. For example, in case the coupling device is used for atransfer of blood, the coupling device may mitigate any loss of bloodand/or a contamination of the environment caused by a leakage in case ofa detachment of the coupling device. Furthermore, by its excellentsealing properties, the coupling device may mitigate any contaminationof the fluid (e.g. blood) transferred through the (connected) couplingdevice.

The present invention is further advantageous in that the couplingdevice provides a convenient detachment (disconnection) of the couplingdevice. For example, if the coupling device is connected to a tube formedical purposes, a pulling of the tube, e.g. by a patient and/ormedical staff, may detach the third housing from the first and/or secondhousing of the coupling device, thereby mitigating any further pullingof the tube at the other end thereof. It will be appreciated that it maybe desirable that (medical) tubes commonly used at hospitals, nursinghomes, clinics, etc., are equipped with a coupling device of the presentinvention, as the coupling device may constitute a “weak link” of thetube. Hence, if a tube is connected between a patient and a source (e.g.an infusion pump or bag) and further comprises a coupling deviceaccording to the present invention, the coupling device may constitutethe “weak link” of the tube where the tube may be “cut off” as a resultof a pulling of the tube.

The coupling device is especially advantageous in case it is provided toa medical tube which in turn is connected to an element inserted into apatient for a transfer of fluid to and/or from the patient. This isrealized as a displacement of the element may not only be painful forthe patient, but may also lead to consequences of the patient'streatment if the transferring of fluid due to the element's displacementis not performed correctly. By the coupling device of the presentinvention, provided to a medical tube for medical purposes, it will beappreciated that equipment connected to the tube such as (infusion)elements, pumps and/or bags, etc., may be spared from damage caused by apulling of the medical tube.

By the coupling device of the present invention, provided to a medicaltube, it will be appreciated that equipment connected to the medicaltube such as (infusion) elements, pumps and/or bags, etc., may be sparedfrom damage caused by a pulling of the medical tube.

The coupling device of the present invention is further advantageous inthat consequences related to medical staff and/or patients trippingand/or falling over (a) medical tube(s) comprising one or more couplingdevices may be mitigated.

The coupling device of the present invention is further advantageous inthat it is easily, conveniently and efficiently (re)connected ifdetached or disconnected. For example, in case a medical tube comprisinga coupling device according to the present invention is pulled apart, itmay be desirable to be able to reinstate the (infusion) therapy again asquickly as possible. The coupling device meets this demand, as the(re)connection of the coupling device may be performed quickly andintuitively due to the innovative configuration of the coupling device.

The coupling device of the present invention is further advantageous inthat its components (e.g. the first, second and/or third housing, thefirst and second sealing elements, etc.) are designed to have relativelysmooth outer surfaces, such that they may be cleaned and/or disinfectedin an easy and efficient manner. For example, after a cleaning and/ordisinfection of a dissembled coupling device, the respective componentsof the coupling device may subsequently be reassembled into the couplingdevice.

The coupling device of the present invention is further advantageous inthat it is relatively inexpensive to manufacture and is easilyassembled. Consequently, the coupling device may primarily be designedfor single-use, i.e. the coupling device may for example be used for onepatient and one therapy (e.g. infusion).

The coupling device of the present invention is further advantageous inthat its design minimizes dead space of the fluid path through thecoupling device, thereby mitigating the occurrence of infectious agents.Furthermore, the inventive design of the coupling device mitigatesleakage of the fluid.

The coupling device of the present invention is further advantageous inthat the flow of fluid through the coupling device is linear along theprincipal axis of the coupling device. In other words, the design of thecoupling device may hereby avoid an undesired turbulence of the fluidduring operation of the coupling device.

By the term “displaceably arranged”, it is here meant that the secondhousing and the third housing may be arranged or mounted within thefirst housing in such a way that they are displaceable or moveablewithin the first housing.

By the term “displaceable arrangement”, it is here meant that the thirdhousing may be arranged or mounted within the first housing in such away that the third housing is displaceable or moveable within the firsthousing.

By the term “releasably connectable”, it is here meant that the secondhousing and the third housing are configured to be attached and detachedby applying a respective force.

By the term “sealingly separate”, it is here meant that the firstsealing element and the second sealing element separate the tube portionand the channel in a sealing manner, such that no fluid can pass betweenthe tube portion and the channel.

According to an embodiment of the present invention, the coupling devicefurther comprises a locking arrangement. In the second position, thesecond housing is releasably connected to the first housing via thelocking arrangement. In other words, when the second housing is in itssecond, refracted position in the first housing, the second housing maybe releasably connected to the first housing. It will be appreciatedthat this position of the second housing implies an enabled transfer offluid through the coupling device, and the present embodiment isadvantageous in that a fluid may be transferred through the device in astationary state of the coupling device, i.e. without the need ofapplying any pressure on one or more components of the coupling device.

According to an embodiment of the present invention, whereby in case ofa force F applied on the third housing connected to the second housingin the second position along the principal axis towards the firstposition exceeds a predetermined threshold, the second housing isconfigured to be released from a connection to the first housing in thesecond position, the second housing is configured to be displaced fromthe second position into the first position, and the third housing isconfigured to be released from the connection to the second housing.Hence, in case of a (pulling) force applied on the third housing (orbetween the third housing and the second housing) exceeds apredetermined threshold, the third housing is configured to detach(disconnect) from the second housing according to the disclosedarrangement. The present embodiment is advantageous in that the thirdhousing and the second housing of the coupling device are onlyconfigured to detach in case the coupling device is subjected to apulling force applied to the third housing which exceeds a predeterminedthreshold value, such that the transfer of fluid through the couplingdevice is interrupted. In other words, the third and second housing areonly configured to separate from each other when exposed to a pullingforce which is relatively strong. Hence, the third and second housing ofthe coupling device are configured to stay connected in case thecoupling device is subjected to a relatively weak force which does notexceed the predetermined threshold value, such that the coupling devicemay remain operative for transferring a fluid.

In case there is provided a tube for medical purposes equipped with acoupling device of the present invention, it will be appreciated thatthe coupling device is further advantageous in that the coupling devicemay be detached before any relatively large force, subjected to aportion of the tube on one side of the coupling device, is transferredto the other portion of the tube, on the other side of the couplingdevice. For example, if an element is connected to the tube, thecoupling device may mitigate any pull, jerk, twitch or the like, of theelement.

The coupling device of the present invention is further advantageous inthat consequences related to medical staff and/or patients trippingand/or falling over tubes comprising one or more coupling devices may bemitigated.

The embodiment is advantageous in that the threshold of the force F canbe conveniently set or determined according to the purpose of thecoupling device. For example, in case a coupling device is used when aneedle is inserted into a patient, the threshold of the force F can bedetermined to be relatively low. In contrast, in case a coupling deviceis used when a urinary catheter is used, the threshold of the force Fcan be determined to be relatively high.

According to an embodiment of the present invention, the coupling devicecomprises a locking mechanism for releasable connection of the thirdhousing to the second housing. The embodiment is advantageous in thatthe third housing may be conveniently connected to (or disconnectedfrom) the second housing by means of the locking element(s).

According to an embodiment of the present invention, in the secondposition of the second housing, the third housing and the second housingare connected by the locking mechanism. Hence, in the second, retractedposition of the second housing, when the tube portion projects throughthe first and second sealing elements and into the passage for enablinga transfer of fluid through the coupling device, the locking mechanismconnects the second and third housings to each other. The embodiment isadvantageous in that the locking mechanism may provide a reliableconnection of the second and third housings to each other, such that thesecond and third housings provide a sealed (leak-proof) transfer offluid through the coupling device.

According to an embodiment of the present invention, the third housingcomprises a first locking element of the locking mechanism, and thesecond housing comprises a second locking element of the lockingmechanism, wherein the first and second locking elements are configuredto releasably lock upon rotation of the first and second lockingelements with respect to each other. For example, the locking mechanismfor connecting the second and third housings according to the present orto any previously disclosed embodiment may comprise a connection of amale-female type. It will be appreciated that the locking mechanism of amale-female type may comprise at least one groove and at least oneprojection configured to project into the at least one groove.

According to an embodiment of the present invention, during adisplacement of the second housing and third housing from the firstposition to the second position, the second locking element isconfigured to rotate with respect to the first locking element formating engagement with the first locking element such that the thirdhousing and the second housing are connected in the second position, andduring a displacement of the second housing and third housing from thesecond position to the first position, the second locking element isconfigured to rotate with respect to the first locking element fordisengaging the mating engagement such that the third housing and thesecond housing are disconnected in the first, extracted position. Inother words, when the second and third housing are pushed into the firsthousing of the coupling device from the first to the second position,the second and third housings connect via a rotation of the first andsecond locking elements with respect to each other. Analogously, whenthe second and third housing are pulled out of the first housing of thecoupling device from the second to the first position, the second andthird housings disconnect via a rotation of the first and second lockingelements with respect to each other

According to an embodiment of the present invention, at least one of thefirst and second sealing elements comprises a resilient membrane. Itwill be appreciated that the resilient membrane(s) is (are) configuredto become arranged (clamped) between the first and second sealingelements upon connection of the second and third housings. Theembodiment is advantageous in that the sealing element(s) may provide anefficient sealing between the second and third housings via theresilient membrane(s) when the second and third housings are connected,such that any leakage between the second and third housings can beavoided.

According to an embodiment of the present invention, the at least oneresilient membrane has a convex shape and is configured to flatten uponabutment of the first sealing element with the second sealing element.In case each of the first and second sealing elements comprises aresilient, convex-shaped membrane, it will be appreciated that themembranes may push away air and form an air-tight seal, furthermoreminimizing dead space, when the membranes are pressed against eachother. Hence, the present embodiment may even further improve thesealing properties of the coupling device.

According to an embodiment of the present invention, the resilientmembrane comprises silicone. The embodiment is advantageous in thatsilicone is particularly suitable for sealing purposes, thereby evenfurther improving the sealing of the coupling device. Furthermore, theuse of silicone of the membrane is advantageous in that the tube portionmay penetrate the membrane without (or at least minimizing a) tearing ofthe material, such that an undesired wear of the membrane and/or acontamination of the fluid in the flow of fluid through the couplingdevice may be avoided.

According to an embodiment of the present invention, the at least oneresilient membrane comprises a through hole, and wherein the at leastone resilient membrane is configured to be arranged into a respectivefitting of the first and/or second sealing element, the size of the atleast one resilient membrane being larger than the fitting such that thethrough hole is configured to be compressed upon arrangement of the atleast one resilient membrane into the fitting. The embodiment isadvantageous in that the tube portion may be guided by the compressedthrough hole upon projection of the tube portion through the sealingelements. The embodiment is further advantageous in that the compressedthrough hole may avoid, or at least minimize, a tearing of the membranematerial upon penetration of the tube portion through the sealingelements.

According to an embodiment of the present invention, the coupling devicefurther comprises an alarm arrangement configured to generate an alarmin case the second housing and the third housing are disconnected. Thepresent embodiment is advantageous in that the alarm arrangement mayquickly and efficiently alert a patient, medical staff and/or otherpersons that the second and third housings of the coupling device havebeen disconnected or detached, and that the fluid transportation throughthe coupling device (and, in case the coupling device is provided to amedical tube, also through the medical tube) has been interrupted.

According to an embodiment of the present invention, the alarm comprisesat least one of a visual alarm and an audible alarm. The presentembodiment is especially advantageous when considering that patientsoften may suffer from impaired eye sight and/or impaired hearing. Thepresent embodiment is further advantageous in that the alarm may alertmedical staff which is not present in the same room as the patient.

According to an embodiment of the present invention, the coupling deviceis configured to generate a tactile feedback to an operator when thesecond housing is in the second position. By the term “tactilefeedback”, it is here meant a physical sensation, alert, or the like,which can be felt by an operator upon handling of the coupling device.For example, the coupling device may be configured to generate a tactilefeedback to an operator when the second housing, in its second position,becomes connected to the first housing. The present embodiment isadvantageous in that an operator may be assured that the coupling deviceis correctly coupled or connected when the second housing is in thesecond, retracted position, as the coupling device hereby is configuredto enable a transfer of liquid through the coupling device.

According to an embodiment of the present invention, there is provided amedical tube for transferring a fluid to or from a patient, wherein themedical tube comprises at least one coupling device according to any oneof the preceding embodiments. In other words, the medical tube maycomprise a first tube portion and a second tube portion, wherein acoupling device may be arranged between the first and second tubeportions. By the term “medical tube” it is here meant substantially anytube for medical purposes, e.g. an infusion tube or urinary catheter.The present embodiment is advantageous in that the medical tube may beconveniently disconnected or detached via the coupling device. Forexample, a pulling of the medical tube, e.g. by a patient and/or medicalstaff, may detach the third housing from the second housing of thecoupling device, thereby mitigating any further pulling of the tube atthe other end thereof. Hence, the medical tube may comprise a “weaklink” by means of the coupling device, which is particularlyadvantageous for medical tubes used at hospitals, nursing homes,clinics, etc.

According to an embodiment of the present invention, there is provided amedical kit comprising at least one medical tube according to theprevious embodiment. The at least one medical tube comprises at leastone coupling arrangement provided at at least one end thereof, and atleast one element connected to the medical tube via the at least onecoupling arrangement. It will be appreciated that the couplingarrangement may be of substantially any type, e.g. a standardizedcoupling which may be possible to couple to many different kinds ofelements. For example, the (medical) element(s) may be an elementarranged for insertion into a patient and configured to transfer a fluidinto, or out from, a patient, such as a needle, cannula, catheter,trocar, or the like. Alternatively, or in addition, the element(s) maybe at least one container arranged to supply a fluid to/from a patientvia the medical tube. The present embodiment is advantageous in that themedical kit may increase the safety during a medical process, e.g. aninfusion process. More specifically, the medical kit may convenientlymitigate effects of a medical tube exposed to forces, e.g. by a pullingof the medical tube by the patient and/or medical staff, and inparticular when the medical tube is connected to an element fortransferring a fluid to and/or from a patient.

Further objectives of, features of, and advantages with, the presentinvention will become apparent when studying the following detaileddisclosure, the drawings and the appended claims. Those skilled in theart will realize that different features of the present invention can becombined to create embodiments other than those described in thefollowing.

BRIEF DESCRIPTION OF THE DRAWINGS

This and other aspects of the present invention will now be described inmore detail, with reference to the appended drawings showingembodiment(s) of the invention.

FIGS. 1a-b are schematic views of a coupling device according to anexemplifying embodiment of the present invention,

FIGS. 2a-d are schematic, cross-sectional views of a coupling deviceaccording to an exemplifying embodiment of the present invention,

FIGS. 3a-b schematically shows locking and unlocking operations of acoupling device according to exemplifying embodiments of the presentinvention,

FIG. 4 schematically shows a disconnection of the coupling device, and

FIG. 5 shows a schematic view of a medical kit according to anembodiment of the present invention.

DETAILED DESCRIPTION

FIGS. 1a-b are schematic views of a coupling device 100 according to anexemplifying embodiment of the present invention. It will be appreciatedthat FIGS. 1a-b are provided for an initial description of the couplingdevice 100, and that a more detailed description of the properties andoperation of the coupling device 100 is provided in the followingfigures and associated text.

The coupling device 100 is provided for the transfer of a fluid Pthrough the coupling device 100 when the coupling device 100 is in itsconnected state. In FIG. 1a , a connection of the coupling device 100has been initiated, which will be described in more detail in thefollowing text and associated figures. In FIG. 1b , a disconnection ofthe coupling device 100 has been initiated. Eventually, the couplingdevice 100 becomes disconnected (detached), whereby the transfer offluid through the coupling device 100 is interrupted.

FIGS. 2a-d are schematic, cross-sectional views of a coupling device 100according to an exemplifying embodiment of the present invention. Itwill be appreciated that the four FIGS. 2a-d disclose exemplifying andmomentary positions of a connection of a coupling device 100 for anincreased understanding of the operation of the coupling device 100.Hence, an analogous disconnection of the coupling device 100 may beanticipated by the reverse order of the figures, and is therefore notpresented in more detail.

FIG. 2a is a schematic view of a coupling device 100 for transferring afluid, wherein the coupling device 100 is shown in a disconnected state.The coupling device 100 comprises a cylinder-shaped first housing 110with an elliptic cross-section, wherein the first housing 110 extendsalong a principal axis A. The first housing 110 comprises a firstopening 120 at a central portion of the back end portion (e.g. a bottompart) of the first housing 110, and a second opening 130 at the frontend portion of the first housing 110. The coupling device 100 furthercomprises a tube portion 140 which extends from the first opening 120 ofthe first housing 110 into the interior of the first housing 110. Theend of the tube portion 140 which point towards the interior of thefirst housing 110 may be formed to be sharp or pointed, and the end ofthe tube portion 140 exemplified in FIG. 2a is beveled. However, the endof the tube portion 140 may alternatively be straight, i.e. without anysharp or pointed end.

The coupling device 100 further comprises a second housing 200 which isenclosed by the first housing 110 and is displaceably arranged withinthe first housing 110 along the principal axis A. It will be appreciatedthat the second housing 200 may be fittingly arranged within the firsthousing 110, e.g. by means of grooves or the like. In FIG. 2a , thesecond housing 200 is positioned in a first (extracted) position withinthe first housing 110. For example, the first, extracted position mayconstitute a position towards (or at) the front end portion of the firsthousing 110. The second housing 200 comprises a first sealing element220, which is exemplified as a cushion or pad-like element arranged atan end of the tube portion 140 of the first housing 110.

The coupling device 100 further comprises a third housing 300 which inthe disconnected state of the coupling device 100 is separate from thefirst housing 110 and second housing 200 of the coupling device 100. Thethird housing 300 comprises a channel 310 which is arranged through thethird housing 300. The third housing 300 further comprises a secondsealing element 320 which is arranged to seal the second channel 310.

It will be appreciated that in the disconnected state of the couplingdevice 100 as shown in FIG. 1a , there can be no passage of fluidthrough the coupling device 100. More specifically, the first sealingelement 220 of the second housing 200 seals the tube portion 140 suchthat there is no passage of fluid through the second housing 200 orfirst housing 110. Analogously, the second sealing element 320 seals thesecond channel 310 such that there is no passage of fluid through thethird housing 300.

The first sealing element 220 and/or the second sealing element 320 maycomprise, or consist of, a respective resilient membrane 600 for sealingpurposes. The membrane 600 may comprise or consist of substantially anymaterial which is suitable for sealing purposes, e.g. silicone.Furthermore, the first sealing element 220 and/or second sealing element320 may have a convex shape. According to an alternative embodiment, theresilient membrane(s) 600 may comprise a through hole, and the resilientmembrane(s) 600 may be configured to be arranged into (a) fitting(s) ofthe first 220 and/or second 320 sealing element (not shown). The size ofthe resilient membrane(s) 600 may hereby be larger than the fitting(s)such that the through hole(s) is (are) configured to be compressed uponarrangement of the resilient membrane(s) 600 into the fitting.

The third housing 300 is insertable into the first housing 110 via thesecond opening 130 of the first housing 110. Hence, the first housing110 is able to receive the third housing 300 via the second opening 130thereof and accommodate the third housing 300 within the first housing110. The first housing 110 and the third housing 300 may have ellipticcross-sections, whereas the second housing 200 may have a circularcross-section. It will be appreciated that the provision of ellipticcross-sections may facilitate the coupling between the housings. Forexample, the third housing 300 may be connected to the second housing200 by a relative arrangement of 0° or 180° between the third housing300 and the second housing 200.

In the exemplifying embodiment of the coupling device 100 in FIG. 2a ,the coupling device 100 comprises a locking mechanism 500 for releasableconnection of the third housing 300 to the second housing 200. The thirdhousing 300 comprises a first locking element 510 of the lockingmechanism 500, wherein the first locking element 510 has the form of oneor more hooks projecting from the third housing 300. The second housing200 comprises a second locking element (not shown) of the lockingmechanism 500 for locking engagement with the first locking element 510of the locking mechanism 500.

The coupling device 100 further comprises a locking arrangement 400 forreleasably locking and/or connecting the second housing 200 to the firsthousing 110. The locking arrangement 400 comprises at least one groove410 in the first housing 110 into which a locking element of the secondhousing 200 is configured to matingly engage (shown in FIG. 3a ). Thelocking arrangement 400 of the coupling device 100 may be configured togenerate a tactile feedback to an operator when the second housing 200is in the second position. For example, the locking arrangement 400 maybe configured to generate a snap and/or click sensation upon locking,such that an operator may be informed or made aware that the secondhousing 200 is connected to the first housing 110 in the secondposition.

FIG. 2b is a schematic view of a coupling device 100 for transferring afluid, wherein the third housing 300 has been inserted in the firsthousing 110 via its second opening 130 and along the principal axis A,as compared to FIG. 2a . Furthermore, in this state or position of thecoupling device 100, the first sealing element 220 of the second housing200 and the second sealing element 320 of the third housing 300 abut.Here, both the first sealing element 220 and the second sealing element320 comprise resilient membranes 600 of convex shape, such that thecentral portions of the respective elements are initially configured tocome into contact upon insertion of the third housing 300 into the firsthousing 110. In this embodiment, the convex-shaped membranes of thefirst and second sealing elements 220, 320 are configured to flattenupon abutment of the first sealing element 220 with the second sealingelement 320. In this manner, the first and second sealing elements 230,320 may sealingly separate the tube portion 140 of the first housing 110and the channel 310 of the third housing 300.

FIG. 2c is a schematic view of a coupling device 100 for transferring afluid, wherein the second housing 200 and the third housing 300 arebeing displaced within the first housing 110. In this depicted currentstate of the coupling device 100, the convex-shaped membranes of thefirst and second sealing elements 220, 320 have flattened as aconsequence of the force between the first sealing element 220 with thesecond sealing element 330, and the original shapes of the convexmembranes are schematically indicated. During the movement of the secondhousing 200 (and the third housing 300) from the first, extractedposition to the second, retracted position of the second housing, thetube portion 140 of the first housing 110 gradually projects through thefirst sealing element 220 and the second sealing element 320 forconnection with the channel 310 for enabling a transfer of fluid throughthe coupling device 100. Furthermore, during this movement, the thirdhousing 300 and the second housing 200 are configured to engagingly andreleasably lock via the locking mechanism upon rotation of the firstlocking element and the second locking element with respect to eachother.

FIG. 2d is a schematic view of a coupling device 100 for transferring afluid, wherein the second housing 200 is positioned in the secondposition in the first housing 110, and the third housing 300 isconnected to the second housing 200. In this position, the third housing300 and the second housing 200 are connected by means of the lockingmechanism (not shown). The tube portion 140 projects or penetratesthrough the first sealing element 220 and the second sealing element320. Furthermore, the tube portion 140 becomes fittingly inserted anddebouches into the channel 310 of the third housing 300. In thisconfiguration of the coupling device 100, a transfer of fluid throughthe coupling device 100 is enabled.

FIG. 3a schematically shows a simplified view of a portion of thecoupling device 100 as previously described. Here, the second housing200 and the third housing 300 have been extracted from the couplingdevice for reasons of understanding of the locking operation of thesecond housing 200 and the third housing 300. The locking mechanism inFIG. 3a comprises a first locking element 510 of the third housing 300,wherein the first locking element 510 comprises two projecting portionseach comprising a groove. The locking mechanism in FIG. 3a furthercomprises a second locking element 520 of the second housing 200,wherein the second locking element 520 comprises two projections. Uponmovement of the third housing 300 towards the second housing 200, asindicated by arrow 535, the second locking element 520 is configured torotate, as indicated by arrow 545, as the result of the second lockingelement 520 being guided by a groove in the first housing (not shown).The second locking element 520 is hereby rotated with respect to thefirst locking element 510 for mating engagement with the first lockingelement 510 such that the third housing 300 and the second housing 200become connected in the second position of the second housing 200. Itwill be appreciated that second housing 200, in the second position, isreleasably connected to the first housing 110 via the at least onegroove 410 (see FIG. 2a ) and the second locking element 520.

Analogously, FIG. 3b schematically shows a simplified view of a portionof the coupling device 100 as previously described, and furthermoreshows an unlocking operation of the second housing 200 and the thirdhousing 300 of the coupling device 100 in a schematic manner. During adisplacement of the second housing 200 and the third housing 300 fromthe second, retracted position to the first, extracted position, asindicated by arrow 555, the second locking element 520 is configured torotate, as indicated by arrow 565, with respect to the first lockingelement 510. As a result, the second locking element 520 disengages themating engagement with the third housing 300. The second locking element520 is hereby rotated with respect to the first locking element 510 suchthat the third housing 300 and the second housing 200 becomedisconnected in the first position of the second housing 200.

FIG. 4 schematically shows a disconnection of the coupling device 100 incase of a force F applied on the third housing 300 along the principalaxis A exceeds a predetermined threshold. FT. In this case, the secondhousing (not shown) is configured to be released from a connection tothe first housing 110 when the second housing is in its second,retracted position. Thereafter, the second housing and the third housing300 are configured to be displaced from the second position into thefirst position, and the third housing 300 is configured to be releasedfrom its connection to the second housing. Eventually, the couplingdevice 100 becomes disconnected (detached), whereby the transfer offluid through the coupling device 100 is interrupted.

It will be appreciated that the coupling device 100 furthermore maycomprise an alarm arrangement (not shown). The alarm arrangement may beconfigured to generate an alarm in case the second housing 200 and thethird housing 300 are disconnected. The alarm may for example comprise avisual alarm and/or an audible alarm. Furthermore, the alarm may becoupled (wirelessly or by wire) to any other equipment used by themedical staff for monitoring the patient(s).

FIG. 5 shows a medical kit 800 according to an embodiment of the presentinvention. The medical kit 800 comprises a medical (e.g. infusion) tube700, which in turn comprises a schematically indicated coupling device100. One or more elements may be connected to the medical tube viacoupling arrangement(s) provided at end portions of the medical tube700, wherein the coupling arrangement(s) may be of standardized type forcoupling to different kinds of elements. For example, and as shown inFIG. 5, an element 810 is connected to an end portion of the medicaltube 700, wherein the element 810 is arranged for insertion into apatient and configured to transfer a fluid to and/or from a patient.Furthermore, at the other end of the medical tube 700, the medical tube700 is coupled to a container 820 (e.g. an infusion bag) arranged tosupply a (infusion) fluid to a patient via the medical tube 700 and theelement 810. It will be appreciated that the medical tube 700 maycomprise a plurality of coupling devices 100 although FIG. 5 merelyshows the use of one coupling device 100 for reasons of simplicity. Thecoupling device 100 may furthermore comprise at least one couplingarrangement, e.g. arranged at one or both ends of the coupling device100, for coupling to different kinds of elements. Furthermore, thecoupling arrangement(s) may be of substantially any type, e.g. astandardized coupling which may be possible to couple to many differentkinds of elements. For example, the coupling arrangement(s) may comprisea coupling of Luer lock type and/or Luer slip type.

The person skilled in the art realizes that the present invention by nomeans is limited to the preferred embodiments described above. On thecontrary, many modifications and variations are possible within thescope of the appended claims. For example, it will be appreciated thatthe figures are merely schematic views of a coupling device 100according to embodiments of the present invention. Hence, anyelements/components of the coupling device may have differentdimensions, shapes and/or sizes than those depicted and/or described.

The invention claimed is:
 1. A coupling device for transferring a fluid, the coupling device comprising: a first housing extending along a principal axis, the first housing comprising a first opening at a back end portion thereof, a second opening at a front end portion thereof, and a tube portion extending from the first opening into the first housing; a second housing displaceably arranged within the first housing along the principal axis between a first position at the front end portion of the first housing and a second position at the back end portion of the first housing, the second housing comprising a first sealing element; and a third housing releasably connectable to the second housing and configured for displaceable arrangement within the first housing along the principal axis, the third housing comprising a channel through the third housing, and a second sealing element arranged to seal the channel, whereby, in the first position of the second housing, the third housing is insertable into the first housing via the second opening thereof, and insertable between the first housing and the first sealing element, such that the first and second sealing elements are configured to abut each other and sealingly separate the tube portion and the channel, and whereby, in the second position of the second housing, the third housing and the second housing are connected and the tube portion projects through the first and second sealing elements for connection with the channel such that a transfer of fluid through the coupling device is enabled.
 2. The coupling device according to claim 1, further comprising a locking arrangement, whereby the second housing, in the second position, is releasably connected to the first housing via the locking arrangement.
 3. The coupling device according to claim 1, wherein when a force (F) applied on the third housing connected to the second housing in the second position along the principal axis towards the first position exceeds a predetermined threshold: the second housing is configured to be released from a connection to the first housing in the second position, the second housing is configured to be displaced from the second position into the first position, and the third housing is configured to be released from a connection to the second housing.
 4. The coupling device according to claim 1, further comprising a locking mechanism configured to releasably connect the third housing to the second housing.
 5. The coupling device according to claim 4, whereby, in the second position of the second housing, the third housing and the second housing are connected by the locking mechanism.
 6. The coupling device of claim 4, wherein the third housing comprises a first locking element of the locking mechanism, and the second housing comprises a second locking element of the locking mechanism, wherein the first and second locking elements are configured to releasably lock upon rotation of the first and second locking elements with respect to each other.
 7. The coupling device of claim 6, wherein, during a displacement of the second housing and third housing from the first position to the second position, the second locking element is configured to rotate with respect to the first locking element for mating engagement with the first locking element such that the third housing and the second housing are connected in the second position, and during a displacement of the second housing and third housing from the second position to the first position, the second locking element is configured to rotate with respect to the first locking element for disengaging the mating engagement such that the third housing and the second housing are disconnected in the first position.
 8. The coupling device according to claim 1, wherein at least one of the first and second sealing elements comprises a resilient membrane.
 9. The coupling device according to claim 8, wherein the resilient membrane has a convex shape which is configured to flatten upon abutment of the first sealing element with the second sealing element.
 10. The coupling device according to claim 8, wherein the resilient membrane comprises silicone.
 11. The coupling device according to claim 1, further comprising an alarm arrangement configured to generate an alarm when the second housing and the third housing are disconnected.
 12. The coupling device according to claim 11, wherein the alarm comprises at least one of a visual alarm or an audible alarm.
 13. The coupling device according to claim 1, wherein the coupling device is configured to generate a tactile feedback to an operator when the second housing is in the second position.
 14. A medical tube for transferring a fluid to or from a patient, wherein the medical tube comprises: at least one coupling device comprising: a first housing extending along a principal axis, the first housing comprising a first opening at a back end portion thereof, a second opening at a front end portion thereof, and a tube portion extending from the first opening into the first housing; a second housing displaceably arranged within the first housing along the principal axis between a first position at the front end portion of the first housing and a second position at the back end portion of the first housing, the second housing comprising a first sealing element; and a third housing releasably connectable to the second housing and configured for displaceable arrangement within the first housing along the principal axis, the third housing comprising a channel through the third housing, and a second sealing element arranged to seal the channel, whereby, in the first position of the second housing, the third housing is insertable into the first housing via the second opening thereof, and insertable between the first housing and the first sealing element, such that the first and second sealing elements are configured to abut each other and sealingly separate the tube portion and the channel, and whereby, in the second position of the second housing, the third housing and the second housing are connected and the tube portion projects through the first and second sealing elements for connection with the channel such that a transfer of the fluid through the at least one coupling device is enabled.
 15. A medical kit, comprising: at least one medical tube comprising: at least one coupling device comprising: a first housing extending along a principal axis, the first housing comprising a first opening at a back end portion thereof, a second opening at a front end portion thereof, and a tube portion extending from the first opening into the first housing: a second housing displaceably arranged within the first housing along the principal axis between a first position at the front end portion of the first housing and a second position at the back end portion of the first housing, the second housing comprising a first sealing element; and a third housing releasably connectable to the second housing and configured for displaceable arrangement within the first housing along the principal axis, the third housing comprising a channel through the third housing, and a second sealing element arranged to seal the channel, whereby, in the first position of the second housing, the third housing is insertable into the first housing via the second opening thereof, and insertable between the first housing and the first sealing element, such that the first and second sealing elements are configured to abut each other and sealingly separate the tube portion and the channel, and whereby, in the second position of the second housing, the third housing and the second housing are connected and the tube portion projects through the first and second sealing elements for connection with the channel such that a transfer of fluid through the at least one coupling device is enabled, at least one coupling arrangement provided at at least one end of the at least one medical tube, and at least one element connected to the medical tube via the at least one coupling arrangement. 